Salivary gland function is regulated by the autonomic nervous system. Alterations in the salivary gland function have been implicated in modifying the rates of dental caries, plaque formation and cystic fibrosis. Prostanglandins (PGs) have been shown to induce salivary secretion and to play important modulating roles in regulating secretory activities during direct stimulation of both branches of the autonomic innervations to salivary glands. Direct effect of PGs on acinar cells will be examined by the studies of effects of PGs on amylase and K release and cyclic AMP accumulation of rat parotid slices. Further characterization of modulating effects of PGs on secretory responses (Na, K, Ca and amylase secretion) during stimulation of both the parasympathetic and sympathetic innervations to parotid and submaxillary glands will be made. Mechanisms of PG-mediated inhibition of NE release during sympathetic nerve stimulation to both glands will be examined. The modulating role of PGs in regulating acetylcholine release during parasympathetic nerve stimulation to parotid gland will be also studied. The nature of PG release following sympathetic nerve stimulation to salivary glands will be investigated. These studies would provide a better understanding of modulating roles of PGs in regulating autonomic activities of salivary glands.